For Belgium: neither. See this thread: for opinions on wearing official looking uniforms - recommended only in Africa, as I recall.
And AOPA is little relevant - the Belgian branch was even discontinued a couple of years ago.
Just make very sure to carry all legal documents, for the rest dress and talk and behave modestly. Prepare your flights thoroughly. Ought to work anywhere, I should think? If you want to fly low, i.e. below the transition altitude of 4500', pay particular attention to military activity on weekdays, there's many danger and reserved zones activated. Check the NOTAM's too, on www.belgocontrol.be
@Lenthamen: I am afraid I cannot confirm your recommendation for EBSP, but it does depend on what one really wants. For myself, the place has too many "new rich people" ("nouveaux riches"), doubtlessly attracted by the F1-circuit. Surely avoid the a/d when there's an actual race, it will be infested by helicopters and no, not Robinsons!
I much prefer nearby EBTX Verviers-Theux: friendly and relaxed, no annoying parajumpers, and quite enjoyable cuisine in the best of Franco-Belgian tradition. The sights around are quite nice indeed, with a couple of river dams, and an army shooting range on the moors ("Hohes Venn" or "Hautes Fagnes")
